public class Square <T> {
    T r;

    public Square(T r) {
        this.r = r;
    }

    public Square() {
    }

    public T getR() {
        return r;
    }

    public void setR(T r) {
        this.r = r;
    }

    @Override
    public String toString() {
        return "Square{" +
                "r=" + r +
                '}';
    }
}
